Building a C64-Pi

This post shows how I’ve transformed a unrepairable* Commodore 64 into a C64-Pi by removing the mainboard and placing a Raspberry Pi inside. The RPi is running the Combian 64 OS, which fast-boots directly into the VICE C64 emulator without showing any boot messages.
This lets me play those good old C64 games in high resolution using my original joystick attached to a C64 “bread bin”!

* by “unrepairable” I mean that the C64 mainboard could not be economically repaired. I have used some of its chips to fix an other C64. 
Just be assured that I didn’t kill a working C64 for this project :-)

Things I used in this project:

  • A “dead” Commodore 64;
    Only the original case and the keyboard are needed.
  • A Raspberry Pi 2 Model B;
    Including a Micro SD card and cable(s) to connect it to a monitor/television.
    Link:
    Raspberry Pi
  • A Keyrah V2 USB interface for classic computer keyboards and joysticks;
    Note: I could also have used the smaller (but more expensive!) C64 keyboard interface sold by Tynemouth Software, but I didn’t know about this product when I built my C64-Pi.
    Link:
    Keyrah V2 (scroll down to bottom for the list of resellers)
    Link:
    C64 USB keyboard kit by Tynemouth Software
  • Combian 64 OS for Raspberry Pi;
    Combian 64 is a special distribution of Raspbian that boots very fast - only a few seconds of black screen without showing any boot messages - and then automatically starts up the VICE C64 emulator, showing you that nice blue **** COMMODORE 64 BASIC V2 **** screen and a blinking cursor. Yay!
    Links:
    Combian 64 homepage + Combian 64 v2.5 download

Photos:

Mounting the Raspberry Pi and the Keyrah into the Commodore 64 case
Side of the C64-Pi showing the Keyrah ports that fit into the original metalwork
The side-connectors of the Raspberry Pi are accessible, but I had to carve away some plastic (probably too much). Maybe next time I’ll use the smaller C64 keyboard interface sold by Tynemouth Software, which allows you to mount the Raspberry Pi into the C64 expansion port hole, which is much larger so you don’t have to carve the case.
Connecting the C64 keyboard -> Keyrah -> Raspberry Pi. Note that the Keyrah also allows you to connect the original LED, which lights up when you push the side-switch into the lowest position
A Commodore 64 with an HDMI output and a USB power input :-)
The C64-Pi boots within 5 seconds to show you a blinking Commodore 64 cursor!

A few gotchas when running Combian 64 / VICE:

  • The VICE emulator in Combian 64 was configured to use the F8-key to enter the VICE main menu. As the Keyrah interface doesn’t map this key, you temporarily need to plug in an additional (standard) USB keyboard, so you can press F8 to go into the VICE menu and change this; from the main menu you should go to “Settings management” -> “Define UI keys” where you can define an alternative “Activate menu” key. Choose some key you won’t normally use, like the pound key (£). Myself I’m using the commodore key (C=) to get into the VICE menu, because I just think that’s the coolest “chicken lips” key on the keyboard :-)
    Note: don’t forget to do a “Save current settings” in the VICE menu to store your changes!
    Note #2: In the “Define UI keys” section, you can also define the keys for menu up/down/left/right/select, which I connected to the joystick in port 2, so I can navigate the menu using my joystick.
  • To use your joystick (connected to the Keyrah!) to play games in VICE, you need to go to the main menu, choose “Machine settings” -> “Joystick settings” -> “Define keysets”, where you can define Keyset 2 (up, down, left, right, fire) by using your joystick in port 2 as input. After defining “Keyset 2", map “Joystick device 2 -> Keyset 2”.
    And don’t forget to “Save current settings” to store your changes.
  • Initially I didn’t get any video output from Combian 64 on my HDMI monitor. It turned out that the video-options in /boot/config.txt were configured for a specific type of display. After I reconnected using the composite video connector (which is combined with the audio jack), I could see the blinking cursor of VICE and quit the emulator to edit the config.txt file.
    To get a minimal (default) config.txt, run this from the command line:
    echo dtparam=audio=on > /boot/config.txt
    and then reboot using 
    shutdown -r now
  • When you want to run games on your C64-Pi, you first need to download some abandonware games in .prg or .d64 format, copy them to a USB stick, and insert the stick into the Raspberry Pi. 
    Then from the Combian 64 command prompt, type “menu” which shows you a menu with some handy tools that Carmelo Maiolino has put together, like the Midnight Commander file manager. Use this tool to copy the files from your USB stick to /root/combian64/games.
    Now start the VICE emulator again and select “Autostart image” from the main menu and navigate to the game you want to start and play!

Have fun!

— DionoiD